Yep, we just went 2 weeks ago and all 3 of my kids need a seat. We took a double and my umbrella. I have a 7, 5 (turned while we were there) and a 2 1/2 yr olds
I would not take one but rent one if needed. The last time we used a stroller was 2 years ago, DD was 3(almost 4) & DS6. We rented a single for DD but had to move up to double only becuase DS got blisters. We have not rented one the past 2 trips and our kids didn't seem to bothered. They did get a little tired but they also slept really well .
We bought a cheap umbrella stroller from Wal-Mart $13 for our DS when he was 6 and our DD was in our proper lie-back one. I was light, doesn't take a lot of space and did the trick. We even used it in DLP last October (almost 3 years after buying it) and it still was perfect - even for getting on and off the buses.